# Calibre

Calibre is the e-book library manager that backs Calibre-Web. It manages metadata, formats, and conversions for the library that Calibre-Web serves.

**Host:** Dankserver (library directory on host) — **Docs:** https://calibre-ebook.com

## Role in this Stack

Calibre itself is a desktop/GUI application, not a container service. This stack runs **Calibre-Web** in a container and points it at an existing Calibre library directory on the Dankserver host.

Calibre is used to:
- Import books into the library (drag-and-drop or CLI `calibredb`)
- Edit metadata (author, title, series, tags, cover art)
- Convert between formats (EPUB → MOBI, MOBI → EPUB, etc.)
- Manage collections and reading lists

The actual library files (`.epub`, `.mobi`, `.pdf`) and the Calibre database (`.db` file) live on the host filesystem. Calibre-Web reads and writes them through the mounted volume.

## Current Version

Calibre 9.2.1 is the version on the live host (9.9.0 is the upstream latest). Major features include:
- Bookshelf view
- Opt-in AI features
- Content server security fix (CVE-2025-7404 equivalent): a bug since v6.16.0 allows any user with server access to read non-Calibre files on the host. Upgrade to 9.9.0+ if serving content to untrusted users.

## Library Directory

| Purpose | Host path (convention) |
|---------|------------------------|
| Calibre library | `/opt/calibre-web/books` (bind-mounted to `/books` in the Calibre-Web container) |

## What the Container Needs

- Read/write access to the library directory. Calibre-Web edits metadata through the database file.
- Ownership matching `PUID=1000` / `PGID=1000` (the `dank` user on Dankserver).

## Optional: Calibre Content Server

Calibre includes a built-in HTTP content server (`calibre-server`) that can serve the library via OPDS feeds and a mobile-friendly web interface. This enables:
- OPDS feeds for mobile reading apps (FBReader, Moon+ Reader)
- Mobile-optimized UI via the `--mobile` flag
- Direct Kindle push

To run as a container:

```yaml
services:
  calibre-server:
    image: lscr.io/linuxserver/calibre:latest
    container_name: calibre-server
    restart: unless-stopped
    environment:
      PUID: "1000"
      PGID: "1000"
      TZ: Etc/UTC
    command: calibre-server --daemonize --port 8080 --enable-auth --url-prefix /calibre /books
    volumes:
      - /opt/calibre-web/books:/books
    ports:
      - "8084:8080"
```

Note: The content server runs headless in `--daemonize` mode. It requires the full Calibre package, not a minimal server.

## See Also

- [[Calibre-Web]] — the containerized frontend
- [[Dankserver Stack]]
- [[ARR-Stack]] — Readarr for automatic ebook downloads